Retractable vehicle step

ABSTRACT

Abstract of the Disclosure 
         
   A retractable step for use with a vehicle comprises a stepping member having a stepping deck, a first arm, a second arm, a motor and a stop.  The first arm has a first end pivotally attached to the vehicle, and a second end pivotally attached to the stepping member.  The second arm also has a first end pivotally attached to the vehicle, and a second end pivotally attached to the stepping member.  The motor is drivingly connected to the first arm such that a rotation of the motor causes rotation of the first arm about its first end and moves the stepping member from a retracted position to an extended position, or vice versa.  The stop is located within the range of motion of the second arm such that the second arm bears against the stop when the stepping member is in the extended position.  The first and second arms are situated such that the first arm is loaded in compression and the second arm is loaded in tension when the stepping member is in the extended position and a load is placed upon it.  In another embodiment, a retractable vehicle step assist comprises a rigid frame, a forward planar linkage pivotably connected to the frame along a forward upper connection width, and a rearward planar linkage pivotably connected to the frame along a rearward upper connection width.  The retractable vehicle step further comprises a rigid step member having a stepping deck.  The step member is pivotably connected to the forward planar linkage along a forward lower connection width, and is pivotably connected to the rearward planar linkage along a rearward lower connection width and on a side of the forward planar linkage opposite the stepping deck.  The stepping deck is substantially wider than any of the forward upper connection width, the rearward upper connection width, the forward lower connection width, and the rearward lower connection width.

Detailed Description of the Invention Related Applications

[0001] This application is a continuation of U.S. Patent Application no.09/817,897, filed March 26, 2001, titled RETRACTABLE VEHICLE STEP, whichclaims the benefit of U.S. Provisional Application no. 60/269,286, filedFebruary 15, 2001, titled RETRACTABLE VEHICLE STEP; and of U.S.Provisional Application no. 60/274,417, filed March 8, 2001, titledRETRACTABLE VEHICLE STEP. The entire contents of each of theabove-mentioned patent applications and prior patent applications arehereby incorporated by reference herein and made a part of thisspecification.

Background of Invention

[0002]

Field of the Invention

[0003] This invention relates generally to a stepping assist for motorvehicles. In particular, the invention relates to a retractable vehiclestep which is movable between a retracted or storage position and anextended position in which it functions as a step assist into thevehicle.

Description of the Related Art

[0004] It is commonly known to add a running board or similar fixedstepping assist to the side of a motor vehicle, especially to a vehiclewith a relatively high ground clearance. However, these fixed runningboards and other stepping assists have had several drawbacks. First, afixed running board is often too high to act as a practical steppingassist and is therefore not very effective in reducing the initial stepheight for the vehicle user. In addition, when using a relatively highrunning board, the user is likely to hit his or her head while climbinginto the vehicle cab. Furthermore, a fixed running board often extends asignificant distance from the side of the vehicle, and can be a sourceof dirt or grime that rubs onto the user"s pants or other clothing asthe user steps out of the vehicle onto the ground surface. Such a fixedrunning board is also frequently struck when the owner of an adjacentparked vehicle opens his door. Finally, a fixed running board or stepreduces the ground clearance of a vehicle, and can often be damaged ortorn off entirely when the vehicle is used for offroad driving.

[0005] Accordingly, a vehicle step which overcomes the above-statedproblems is desired.

Summary of Invention

[0006] In accordance with one preferred embodiment, a retractable stepfor use with a vehicle comprises a stepping member having a steppingdeck, a first arm, a second arm, a motor and a stop. The first arm has afirst end pivotally attached to the vehicle, and a second end pivotallyattached to the stepping member. The second arm also has a first endpivotally attached to the vehicle, and a second end pivotally attachedto the stepping member. The motor is drivingly connected to the firstarm such that a rotation of the motor causes rotation of the first armabout its first end and moves the stepping member from a retractedposition to an extended position, or vice versa. The stop is locatedwithin the range of motion of the second arm such that the second armbears against the stop when the stepping member is in the extendedposition. The first and second arms are situated such that the first armis loaded in compression and the second arm is loaded in tension whenthe stepping member is in the extended position and a load is placedupon it.

[0007] In accordance with another embodiment, a retractable vehicle stepassist comprises a rigid frame, a forward planar linkage pivotablyconnected to the frame along a forward upper connection width, and arearward planar linkage pivotably connected to the frame along arearward upper connection width. The retractable vehicle step furthercomprises a rigid step member having a stepping deck. The step member ispivotably connected to the forward planar linkage along a forward lowerconnection width, and is pivotably connected to the rearward planarlinkage along a rearward lower connection width and on a side of theforward planar linkage opposite the stepping deck. The stepping deck issubstantially wider than any of the forward upper connection width, therearward upper connection width, the forward lower connection width, andthe rearward lower connection width.

[0008] In accordance with yet another preferred embodiment a retractablevehicle step assist for use with a vehicle having two adjacent doorsthrough which persons may enter the vehicle, comprises a rigid frame, astep member having a stepping deck, and at least two rigid armsconnecting the step member to the frame and allowing the step member tomove between a retracted position near the frame to a deployed positiondownward and away from the frame. The stepping deck is of sufficientwidth to provide a step for persons desiring to enter either of thedoors.

[0009] In accordance with still another preferred embodiment, aretractable vehicle step assist for use with a vehicle having twoadjacent doors through which persons may enter the vehicle, comprises arigid frame and a step member having a stepping deck. The retractablestep assist further comprises at least two rigid arms connecting thestep member to the frame and allowing the step member to move between aretracted position near the frame to a deployed position downward andaway from the frame. The stepping deck extends in front of each of thedoors when in the deployed position.

[0010] In accordance with still another preferred embodiment, aretractable vehicle step assist comprises a rigid frame, a step memberhaving a stepping deck, and at least two rigid arms connecting the stepmember to the frame and allowing the step member to move between aretracted position near the frame to a deployed position downward andaway from the frame. The stepping deck is substantially wider than theframe.

[0011] In accordance with still another preferred embodiment, aretractable vehicle step assist comprises a rigid frame, a step memberhaving a stepping deck, and a forward rigid arm and a rearward rigid armconnecting the step member to the frame and allowing the step member tomove between a retracted position near the frame to a deployed positiondownward and away from the frame. The step member is pivotably connectedto the rearward rigid arm at a rearward pivotable connection and thestep member rotates downward about the rearward pivotable connection asthe step member moves to the deployed position.

[0012] In accordance with still another preferred embodiment, aretractable vehicle step assist comprises a rigid frame, a step memberhaving a stepping deck, and at least two rigid arms connecting the stepmember to the frame and allowing the step member to move between aretracted position near the frame to a deployed position downward andaway from the frame. The stepping member further comprises a supportbracket rigidly connected to the stepping deck and connected to the armsopposite the stepping deck. The support bracket is oriented at an angleto the stepping deck.

[0013] In accordance with still another preferred embodiment, a methodof improving access to a vehicle through a door of the vehicle,comprises attaching a rigid frame to the vehicle, and connecting astepping member having a stepping deck to the frame via at least tworigid arms. This is done so that the stepping member is moveable betweena retracted position near the frame to a deployed position wherein thestepping deck is situated along the side of the vehicle below the door.In the method the stepping deck is substantially wider than the frame.

[0014] In accordance with another embodiment, a retractable vehicle stepassembly comprises a step member having a stepping deck and a bracketextending inboard from the stepping deck. The assembly further comprisesa first unitary support arm defining an inboard surface and an outboardsurface. A maximum distance between the inboard surface and the outboardsurface defines a first thickness, and the first support arm defines asubstantially vertical first side and a substantially vertical secondside. A maximum distance between the first side and the second sidedefines a first width, and the first width is substantially greater thanthe first thickness. The assembly further comprises a second unitarysupport arm defining an inboard surface and an outboard surface. Amaximum distance between the inboard surface and the outboard surfacedefines a second thickness. The second support arm defines asubstantially vertical first side and a substantially vertical secondside, and a maximum distance between the first side and the second sidedefines a second width. The second width is substantially greater thanthe second thickness. The first support arm and the second support armare connectable with respect to an underside of a vehicle so as to bepivotable about a first axis and a second axis, respectively. The firstsupport arm and the second support arm are connected to the step memberso that the first support arm and the second support arm are pivotablewith respect to the bracket about a third axis and a fourth axis,respectively, the fourth axis being located inboard from the third axis.The first support arm and the second support arm allow the step memberto move between a retracted position and a deployed position downwardand outboard from the retracted position. The stepping deck furthercomprises an upper surface which defines a plane for supporting at leastthe forefoot of a user. The angle of the plane with respect to thehorizontal varies as the step member moves between the retractedposition and the deployed position. The first axis is spaced from thethird axis by a first distance, and the second axis is spaced from thefourth axis by a second distance. The first distance and the seconddistance are unequal. The bracket is entirely supported by the firstsupport arm and the second support arm when the step member is in thedeployed position.

[0015] In accordance with another embodiment, a retractable vehicle stepassist comprises a step member having a stepping deck and a supportbracket portion extending inboard from the stepping deck. The stepassist further comprises a first unitary support arm defining an inboardsurface and an outboard surface, and a maximum distance between theinboard surface and the outboard surface defines a first thickness. Thefirst support arm defines a substantially vertical first side and asubstantially vertical second side, a maximum distance between the firstside and the second side defining a first width. The first width issubstantially greater than the first thickness. The step assist furthercomprises a second unitary support arm defining an inboard surface andan outboard surface, and a maximum distance between the inboard surfaceand the outboard surface defines a second thickness. The second supportarm defines a substantially vertical first side and a substantiallyvertical second side, and a maximum distance between the first side andthe second side defines a second width. The second width issubstantially greater than the second thickness. The first support armand the second support arm are connectable with respect to an undersideof a vehicle so as to be pivotable about a first pivot axis and a secondpivot axis, respectively. The first support arm and the second supportarm are connected to the step member so that the first support arm andthe second support arm are pivotable with respect to the step memberabout a third pivot axis and a fourth pivot axis, respectively. Thefourth pivot axis is located inboard from the third pivot axis. Thefirst support arm and the second support arm allow the step member tomove between a retracted position and a deployed position downward andoutboard from the retracted position. The stepping deck furthercomprises an upper surface which defines a plane for supporting at leastthe forefoot of a user. The angle of the plane with respect to thehorizontal varies as the step member moves between the retractedposition and the deployed position. The first pivot axis is spaced fromthe third pivot axis by a first distance, and the second pivot axis isspaced from the fourth pivot axis by a second distance. The firstdistance and the second distance are unequal. The support bracketportion provides a recessed area into which the first support arm isinserted at the third pivot axis.

[0016] In accordance with another embodiment, a retractable vehicle stepassist comprises a step member having a stepping deck and a supportbracket portion extending inboard from the stepping deck. The stepassist further comprises a first unitary support arm defining an inboardsurface and an outboard surface, and a maximum distance between theinboard surface and the outboard surface defines a first thickness. Thefirst support arm defines a substantially vertical first side and asubstantially vertical second side, a maximum distance between the firstside and the second side defining a first width. The first width issubstantially greater than the first thickness. The step assist furthercomprises a second unitary support arm defining an inboard surface andan outboard surface, and a maximum distance between the inboard surfaceand the outboard surface defines a second thickness. The second supportarm defines a substantially vertical first side and a substantiallyvertical second side, and a maximum distance between the first side andthe second side defines a second width. The second width issubstantially greater than the second thickness. The first support armand the second support arm are connectable with respect to an undersideof a vehicle so as to be pivotable about a first pivot axis and a secondpivot axis, respectively. The first support arm and the second supportarm are connected to the step member so that the first support arm andthe second support arm are pivotable with respect to the step memberabout a third pivot axis and a fourth pivot axis, respectively. Thefourth pivot axis is located inboard from the third pivot axis. Thefirst support arm and the second support arm allow the step member tomove between a retracted position and a deployed position downward andoutboard from the retracted position. The stepping deck furthercomprises an upper surface which defines a plane for supporting at leastthe forefoot of a user. The angle of the plane with respect to thehorizontal varies as the step member moves between the retractedposition and the deployed position. The first pivot axis is spaced fromthe third pivot axis by a first distance, and the second pivot axis isspaced from the fourth pivot axis by a second distance. The firstdistance and the second distance are unequal. The support bracketportion provides an opening in an upper surface of the support bracketportion into which opening the first support arm is inserted at thethird pivot axis.

[0017] All of these and other embodiments are intended to be within thescope of the invention herein disclosed. This and other embodiments ofthe present invention will become readily apparent to those skilled inthe art from the following detailed description of the preferredembodiments having reference to the attached figures, the invention notbeing limited to any particular preferred embodiment or embodimentsdisclosed.

Brief Description of Drawings

[0018] Having thus summarized the general nature of the invention andits essential features and advantages, certain preferred embodiments andmodifications thereof will become apparent to those skilled in the artfrom the detailed description herein having reference to the figuresthat follow, of which:

[0019]Figure 1 is a side elevation view of a retractable vehicle step inaccordance with one preferred embodiment of the invention;

[0020]Figure 2 is a front elevation view of the retractable vehicle stepof Figure 1;

[0021]Figure 3 is a side elevation view of a retractable vehicle step inaccordance with another preferred embodiment of the invention, in thedeployed position;

[0022]Figure 4 is an exploded perspective view of the retractablevehicle step of Figure 3;

[0023]Figure 5 is a side elevation view of the retractable vehicle stepof Figure 3, in the retracted position; and

[0024] Figures 6A-6B are perspective views of the retractable vehiclestep as used in connection with a vehicle.

Detailed Description of the Preferred Embodiments

[0025] As a preliminary matter, it should be noted that the termsforward, front and outboard are used interchangeably herein, as are theterms rearward, rear and inboard, when describing components of the stepstructures disclosed herein. These terms are to be understood withreference to a direction of ingress into a vehicle,forward/front/outboard meaning generally toward the exterior of thevehicle, and rearward/rear/inboard meaning generally toward the interiorof the vehicle.

[0026] Figures 1 and 2 depict the lower portion of a vehicle 10 havingan underbody 12, an exterior 14, a vertical underbody portion 16 and anunder panel 18. A retractable vehicle step 20 is shown associated withthe vehicle 10. Referring specifically to Figure 2, the retractablevehicle step 20 has a stepping member 22, which consists of a steppingdeck 24 with an outboard end 24a, an inboard end 24b, integrally formedsupport brackets 26a, 26b, and drive brackets 28a, 28b located inward ofthe support brackets 26a, 26b. The support brackets 26a, 26b arepivotally connected to support arms 30a, 30b via clevis pins 32a, 32b,at an end of the support brackets 26a, 26b opposite the stepping deck24. Similarly, the support arms 30a, 30b are pivotally connected toanchor brackets 34a, 34b via clevis pins 36a, 36b, at an end of eachsupport arm opposite the support brackets 26a, 26b. The anchor brackets34a, 34b are rigidly connected to the underbody 12 by welding, bolting,riveting or other techniques known to those skilled in the art.

[0027] The drive brackets 28a, 28b of the stepping member 22 arepivotally connected to a drive arm 38 via clevis pins 40a, 40b, at anend of the drive brackets 28a, 28b opposite the stepping deck 24. Asbest seen in Figure 2, the drive arm 38 preferably has an Hconfiguration and is pivotally connected to anchor brackets 42a, 42b viaclevis pins 44a, 44b at an end of the drive arm 38 opposite the drivebrackets 28a, 28b. The anchor brackets 42a, 42b are rigidly connected tothe underbody 12 by welding, bolting, riveting or other techniques knownto those skilled in the art.

[0028] Accordingly, the retractable vehicle step 20 defines thefollowing axes of rotation, best seen in Figure 2: a first axis A-Aabout which the support arms 30a, 30b rotate with respect to theunderbody 12 and/or anchor brackets 34a, 34b; a second axis B-B aboutwhich the drive arm 38 rotates with respect to the underbody 12 and/oranchor brackets 42a, 42b; a third axis C-C about which the support arms30a, 30b and support brackets 26a, 26b rotate with respect to eachother; and a fourth axis D-D about which the drive arm 38 and the drivebrackets 28a, 28b rotate with respect to each other. Figure 1, as a sideelevation view of Figure 2, depicts the axes A-A, B-B, C-C, D-D aspoints. The first axis A-A is spaced from the third axis C-C by a firstdistance X and the second axis B-B is spaced from the fourth axis D-D bya second distance Y. (In other words, the first axis A-A is spaced fromthe rotatable connection of the support arms 30a, 30b to the step member22 by the first distance X, and the second axis B-B is spaced from therotatable connection of the drive arm 38 to the step member 22 by thesecond distance Y.) In one embodiment, the first and second distances X,Y are unequal; in another embodiment the first distance X is greaterthan the second distance Y. In one embodiment, the first axis A-A islocated upward from the second axis B-B.

[0029] With reference now to Figure 1, a motor 46 is rigidly mounted tothe underbody 12 on a mounting bracket (not shown) adjacent theretractable vehicle step 20. The motor 46 turns a pinion gear 48 aboutan axis roughly parallel to the plane defined by the underbody 12. Thepinion gear 48 meshes with drive teeth 50 formed at the end of the drivearm 38. Actuation of the motor 46 causes the pinion gear 48 to rotateand the drive arm 38 to counter-rotate with respect to the motor 46 andpinion gear 48, about the clevis pin 44a. As the drive arm 38 rotates itpushes the stepping member 22 by virtue of its connection to the drivebrackets 28a, 28b. Thus, when the motor 46 is caused to rotate, themotor 46 moves the retractable vehicle step 20 between a retractedposition A wherein the stepping deck is desirably generally positionedinward from the exterior of the vehicle or fixed running board and anextended position B in which the stepping deck is extended sufficientlyto provide a step for at least the forefoot portion of a user"s foot. Asthe retractable vehicle step 20 moves between the retracted position Aand the extended position B under the power of the motor 46, the supportarms 30a, 30b rotate with respect to the clevis pins 36a, 36b and 32a,32b and support and guide the motion of the retractable vehicle step 20.The extended position B is reached when the support arms 30a, 30bcontact a stop 52 which is preferably mounted on the vertical underbodyportion 16. In one embodiment (best seen in Figure 1), the stepping deck24 is tilted upward when in the retracted position A, with the outboardend 24a located upward from the inboard end 24b.

[0030] When the retractable vehicle step 20 is in the extended positionB, a downward force exerted on the stepping deck 24 causes the supportarms 30a, 30b to bear against the stop 52. This arrangement causes theload on the stepping deck 24 to be borne primarily by the supportbrackets 26a, 26b, support arms 30a, 30b and the stop 52. In theextended position B, the retractable vehicle step 20 takes on a geometrysuch that the support brackets 26a, 26b, and support arms 30a, 30b areloaded in tension. The clevis pins 32a, 32b define a pivot axis of thestepping member 22. The torque generated by a load on the stepping deck24 is opposed by the drive arm 38, which is thus loaded in axialcompression between the clevis pins 40a, 40b and 44a, 44b. Because theclevis pins 44a, 44b are fixed in the anchor brackets 42a, 42b, themotor 46 is isolated from the load on the stepping deck 24.

[0031] This aspect of the retractable vehicle step 20 prevents damage tothe motor by eliminating back-loading, as there is no torque reactionabout the end of the drive arm 38, even when very heavy loads are placedon the stepping deck 24. Thus the motor 46 is not needed to exert acounter-torque on the drive arm 38 to support the load on the steppingdeck 24. This feature also eliminates the need for balky, unreliableclutches or any other means of disconnecting the motor 46 from theretractable vehicle step 20, or retractable stops or the like to engageand support the vehicle step 20 when in the extended position.

[0032] The retractable vehicle step 20 functions in this manner when inthe extended position B so long as the drive arm 38 is rotated furtheraway from the vertical in a counterclockwise direction (as shown inFigure 1) than are the support arms 30a, 30b. That is, when the drivearm 38 is parallel to, or displaced clockwise beyond parallel to, thesupport arms 30a, 30b, the drive arm 38 will not maintain the supportarms 30a, 30b against the stop 52. Rather, the retractable vehicle step20 will tend to move toward the retracted position A, and the drive arm38 will tend to rotate counterclockwise (in Figure 1) about the clevispins 44a, 44b. In this situation the motor 46 would be needed to exert acounter-torque on the drive arm 38, to maintain the retractable vehiclestep 20 in the extended position B. As mentioned above, it isundesirable to require the motor 46 to function in this manner.

[0033] A dust cover or cap 54 may be mounted to the lower body panel 18to provide a storage location for the stepping member 22 and preventdust or grime from collecting on the stepping deck 24.

[0034] With these features the retractable vehicle step 20 provides apractical stepping assist for a vehicle user, which can be quickly movedinto an extended position for use and retracted out of the way whennecessary. As detailed above, this functionality is provided with aminimum of mechanical complexity and a high level of reliability.Moreover, the retractable vehicle step 20 is easily connected to avehicle"s existing systems to allow even greater usability. For example,the motor 46 may be connected to the vehicle"s electrical system tocause the vehicle step 20 to quickly move to the extended position uponshutting off the vehicle"s engine, placing the vehicle in park, openinga door, or signaling the power door-lock system with a remote device orcontrol such as a key fob control. Similarly, the motor 46 may besignaled to retract the vehicle step upon starting the engine, placingthe vehicle in drive, closing or locking the door(s) with which the stepis associated, etc.

[0035] Another embodiment of a retractable vehicle step 120 is shown inFigures 3-5. The retractable step 120 comprises a stepping member 122that includes a stepping deck 124 bolted or otherwise rigidly connectedto a support bracket 126. The stepping deck 124 has an outboard end 124aand an inboard end 124b. Front and rear support arms 130a, 130b arerotatably connected to the support bracket 126 via pins 132a, 132b. Arigid frame 134, which may be configured as necessary for connection tothe vehicle underbody 12, provides a secure mounting for the supportarms 130a, 130b which are rotatably mounted to the frame 134 via pins136a, 136b.

[0036] As with the embodiment shown in Figures 1-2, the retractablevehicle step 120 depicted in Figures 3-5 defines the following axes ofrotation, best seen in Figure 4: a first axis A-A about which the frontsupport arm 130a rotates with respect to the underbody 12 and/or frame134; a second axis B-B about which the rear support arm 130b rotateswith respect to the underbody 12 and/or frame 134; a third axis C-Cabout which the front support arm 130a and support bracket 126 rotatewith respect to each other; and a fourth axis D-D about which the rearsupport arm 130b and support bracket 126 rotate with respect to eachother. Figure 3, as a side elevation view of Figure 4, depicts the axesA-A, B-B, C-C, D-D as points. The first axis A-A is spaced from thethird axis C-C by a first distance X and the second axis B-B is spacedfrom the fourth axis D-D by a second distance Y. (In other words, thefirst axis A-A is spaced from the rotatable connection of the frontsupport arm 130a to the step member 122 by the first distance X, and thesecond axis B-B is spaced from the rotatable connection of the rearsupport arm 130b to the step member 22 by the second distance Y.) In oneembodiment, the first and second distances X, Y are unequal; in anotherembodiment the first distance X is greater than the second distance Y.In one embodiment, the first axis A-A is located upward from the secondaxis B-B.

[0037] As best seen in Figure 4, each of the support arms 130 comprisesa generally planar, unitary member which forms two coaxial bearingmembers 131 at either end thereof. The coaxial bearing members maycomprise coaxial bores which engage pins in the frame and step member torotatably connect the support arm to each. In other embodiments thecoaxial bearing members may comprise coaxial axle portions which engagebores formed in the frame/step member to provide the rotatableconnections. Alternatively, one or both of the support arms may form asingle bearing member at one or both ends, comprising a singlefull-width bore or a single, central partial-width bore.

[0038] The spacing of the coaxial bearing members 131 defines aconnection width CW at each end of each support arm. The connectionwidth represents the distance between the opposite ends of theengagement of the bearing members with the frame/stepping member. Forexample, in Figure 4 the support arm 130a is rotatably connected to theframe along an upper connection width, which equals the distance betweenthe outer edges of the coaxial bearing members 131. The support arm 130ais connected to the step member along a lower connection width. Thesupport arm 130b likewise defines an upper connection width and a lowerconnection width. These four connection widths are shown in Figure 4 asbeing approximately equal, but they may be varied in relative size asdesired.

[0039] The support arms 130a, 130b also include a rigid crosspiece 133interconnecting the bearing members 131. The crosspiece isadvantageously of sufficient strength to prevent the support arms 130a,130b from substantially deflecting from their planar configuration whena user steps on the stepping deck 124. The crosspiece may take on anysuitable configuration, such as the full-size member shown, or a seriesof individual cross members extending horizontally or diagonally in an Xpattern, etc. The high rigidity of the crosspiece and the arms 130a,130b as a whole advantageously permits the width of the arms to beminimized while nonetheless providing stable support for the steppingdeck 124 when in the extended position.

[0040] The front and rear support arms may take on other forms andconfigurations so long as each comprises a generally planar linkageconnecting the step member to the frame. A generally planar linkage mayadvantageously comprise a generally planar, unitary member such assupport arm 130a or support arm 130b as shown in Figure 4. Analternative generally planar linkage comprises two or more separate arms(employed in place of a single unitary arm) interconnecting the frameand step member, the arms being coplanar by virtue of a common upperaxis of rotation associated with rotatable connection of the arms to theframe, and a common lower axis of rotation associated with rotatableconnection of the arms to the step member opposite the frame. As with aunitary arm, a multiple-arm planar linkage defines at either end thereofa connection width extending between the outer edges of the coaxialbearing members formed by the outermost arms making up the linkage.

[0041] With further reference to Figures 3 and 4, the support bracket126 may comprise any suitable structural member having sufficientrigidity to resist bending about its horizontal and longitudinal axes.Thus the box configuration shown in Figure 4 is particularly suitable,but those skilled in the art will appreciate that the bracket 126 cantake on other shapes known to those skilled in the art. The relativelysmall connection width of the arms 130 permits the bracket 126 to bemade of minimal width as well. By making the bracket 126 of sufficientlength, the stepping deck 124 will be positioned properly for easy usewhen the step 120 is in the deployed position (see Figure 3) and thelength of the arms 130 can be kept to a minimum.

[0042] Referring now to Figure 4, the depicted support bracket 126comprises a unitary member forming an upper surface 127, lower surface129 and first and second side segments 141, 143. In the illustratedembodiment, the upper surface 127 forms an opening 145 through which thelower portions of the first and second support arms 130a, 130b may beinserted, into a recessed area 149 bounded by the lower surface 129 andthe first and second side segments 141, 143. In other words, the firstand second support arms 130a, 130b are inserted into the opening 145 orrecessed area 149 at the third and fourth axes C-C, D-D, respectively.

[0043] As best seen in Figure 3, the support bracket 126 preferablyforms an angle with the stepping deck 124, and thus extends upward andrearward from the substantially level (when in the extended position)upper surface of the deck 124. Consequently, the preferred angledconfiguration further enables the length of the support arms 130 to beminimized. The step member 122 may thus be said to move between anupward-rotated orientation in the retracted position (Figure 5) to adownward-rotated orientation in the deployed position (Figure 3). Inother words, the step member 122 rotates downward about its connectionwith the support arm 130b when moving to the deployed position, androtates upward about the same connection when moving to the retractedposition. When in the retracted position the stepping deck 124 tiltsupward (with the outboard end 124a located upward from the inboard end124b), minimizing the total downward protrusion of the retractable stepfrom the vehicle underbody. Preferably, this upward tilt is at least20º, to facilitate any water or debris draining off the step and therebyenhance its safety when in use.

[0044] With the stepping member 122 moveably connected to the frame 134via the support arms 130a, 130b, it can be moved between the retractedposition A and the extended position B, as shown in Figures 5 and 3,respectively. As with the embodiment described previously, theretractable step 120 provides a sturdy step for a vehicle user when inthe extended position B. The geometry of the stepping member 122,support arms 130, and frame 134 causes the arm 130a to be loaded intension and the arm 130b to be loaded in compression when a load isapplied to the stepping deck 124 in a manner similar to that shown inFigure 1. Accordingly, the arm 130b urges the arm 130a against a stop152 when a user steps on the stepping deck 124, by applying a horizontalreaction force to the step member 122. The stop 152 prevents motion ofthe drive arm 138 beyond a location chosen so that when the drive arm138 strikes the stop 152, the step 120 is in a configuration where ittends to move further away from the retracted position upon applicationof a load to the stepping deck 124, but is prevented from doing so byvirtue of the stop. Due to this convergence of factors, the extendedstep 120 firmly maintains its deployed position in which the supportbracket 126, and therefore the step member 122, are for practicalpurposes entirely supported by the support arms 130a and 130b, withoutinput from motor 146 (discussed in further detail below), when steppedupon by a user. This feature eliminates the need for a separate lockingmechanism, often seen in the form of a hydraulic lock, to maintain thestepping deck in the deployed position when in use. Consequently, thisfeature enhances the ease of use of the retractable step, as the user isnot required to operate or disengage the lock when retracting ordeploying the step, thereby eliminating an undesirable aspect ofprior-art retractable step systems.

[0045] A drive system 137 provides powered movement of the step 120between the retracted and the extended position. The drive system 137comprises a drive arm 138 coupled to a rotor 139, both of which arerotatably mounted on the pin 136a, and a motor 146 drivingly connectedto the drive arm 138 via the rotor 139. The drive arm 138 is connectedto the rotor 139 so as to rotate in concert therewith about the pin136a. In another embodiment, the rotor and drive arm form an integralunit.

[0046] The motor 146 can be mounted to the frame 134, to the vehicleunderbody, or in any other suitable location. The motor 146 drives therotor, drive arm, stepping member, etc. via, for example, a worm gear147 that meshes with teeth (not shown) formed on the circumference ofthe rotor 139. In another embodiment, the motor may comprise a linearactuator that pushes or pulls on the circumference of the rotor 139 inorder to rotate it in either direction. Of course, any suitable means ofcoupling the motor to the rotor/drive arm may be used. Advantageously, awindow motor may be used to drive the apparatus. Preferably, the motorwill adjust for changes in temperature.

[0047] The drive system 137, or any drive system employed with any ofthe embodiments of the retractable step disclosed herein, mayadvantageously include a system to stop the motion of the step member,arms, etc. when an obstruction is encountered within the range of motionof the step, or within the moving parts of the step. Such a systemreduces the risk of a pinching injury when a person has inadvertentlyinserted his or her hand, arm, etc. within the mechanism, and alsoreduces the potential for damaging the step member or other parts of theretractable step when it approaches or strikes a hard object such as acurb. It is contemplated that a standard anti-pinch/anti-strike systemmay be used, as is known in the art.

[0048] A dust cover or cap 154 may be mounted to the lower body panel 18to provide a storage location for the stepping member 122 and preventdust or grime from collecting on the stepping deck 124. The dust cover154 advantageously has a portion that protrudes downward from the lowersurface of the vehicle and extends across the gap formed between theupper surface of the deck 124 and the adjacent vehicle structure, andmay extend or curl around the outer edge of the deck 124. Thus the dustcover 154 forms a protective pocket around the outer edge and uppersurface of the deck 124. It has been found that the dust cover 154reduces the accumulation of water, dust, mud and/or debris on the deck,providing a substantial benefit in terms of safety and aesthetics whilereducing the chance of soiling the user"s clothes when he or she stepson or stands near the deck.

[0049] The retractable step thus utilizes a relatively compact linkagesystem to support the stepping deck 124 when in the deployed position.The relatively short, compact support arms 130 can be made of minimalwidth, as can the frame 134 and support bracket 126. The stepping deck124 can thus be made substantially wider than the frame/supportarms/support bracket. In other words the stepping deck 124 is preferablysubstantially wider than any of the connection width(s) defined by thesupport arms. Advantageously, the stepping deck is about 2-8 times aswide as the frame, support arms, support bracket or any of theconnection width(s) defined by the support arms. Thus the retractablestep provides a wide stepping deck for the vehicle user while minimizingthe width and space requirements of the frame, linkage system, etc.

[0050] The wide stepping deck 124 and relatively narrow frame/supportarms/support bracket permit a single retractable step to serve as aconvenient step assist for two adjacent doors of a vehicle, withoutoccupying a large amount of space under the vehicle with the frame,support arms and support bracket. Figure 6A shows a vehicle 200 havingon one side thereof a front door 202 and an adjacent rear door 204. InFigure 6A no portion of the retractable vehicle step is visible becauseit is in the retracted position. Figure 6B shows the stepping deck 124of the retractable step after it has moved to the extended position(upon opening the front door 202 or in response to other actions asdetailed above). It is readily seen that the deck 124 provides aconvenient step assist for a person desiring to enter the vehiclethrough either of the doors 202, 204. Where the deck 124 extends infront of about 1/4 of the width of each door, the deck will besufficiently wider than the user"s foot to provide an easy-to-use step.Extending the deck to cover about 1/2 the width of each door provides anadditional safety factor above a 1/4-width deck. A deck which extendsacross substantially the entire width of both doors is most advantageousin that it essentially eliminates the need for the user to look down tothe step when placing a foot upon it, facilitating easy use by a personcarrying a large number of items with them.

[0051] More broadly stated, the novel configuration of the retractablestep permits the width of the stepping deck to be selected largelyindependently of the width of the frame, arms and/or support bracket.Consequently, a stepping deck that is intended to serve as a step fortwo adjacent doors need not extend the entire width of the doors. It mayinstead be only about 4-5 feet wide (in comparison to a standard fixedrunning board which is typically 6-8 feet in width), providing aconvenient step while keeping the size and weight of the overall deviceto a minimum. It has been found that this particular width provides anoptimal balance between providing ease of use (via a relatively widedeck) and avoiding an overly large, bulky device. Likewise, the steppingdeck of a retractable step intended for use with a single vehicle doormay be reduced to an optimal deck width which is less than the entirewidth of the door.

[0052] Accordingly the retractable step of the present inventiondelivers benefits in terms of space utilization, convenience,reliability and economy.

[0053] Although this invention has been disclosed in the context ofcertain preferred embodiments and examples, it will be understood bythose skilled in the art that the present invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the invention and obvious modifications and equivalentsthereof. Thus, it is intended that the scope of the present inventionherein disclosed should not be limited by the particular disclosedembodiments described above, but should be determined only by a fairreading of the claims that follow.

What is Claimed is:
 1. 50. A retractable vehicle step, comprising: astep member having a stepping deck and a support bracket portionextending inboard from said stepping deck; a first support arm; and asecond support arm; said first support arm and said second support armconnectable with respect to an underside of a vehicle so as to bepivotable about a first pivot axis and a second pivot axis,respectively; said first support arm and said second support armconnected to said step member so that said first support arm and saidsecond support arm are pivotable with respect to said step member abouta third pivot axis and a fourth pivot axis, respectively, said fourthpivot axis located inboard from said third pivot axis; said firstsupport arm and said second support arm allowing said step member tomove between a retracted position and a deployed position downward andoutboard from said retracted position; said first support arm and saidsecond support arm extending downward and outboard from said first andsecond pivot axes, respectively, when said step member is in saidretracted position; wherein said stepping deck is substantially widerthan said support bracket portion; wherein said support bracket portionprovides a recessed area into which said first support arm is insertedat said third pivot axis.
 2. 51. The retractable vehicle step of Claim50, wherein said support bracket portion provides an opening in an uppersurface of said support bracket portion into which opening said firstsupport arm is inserted at said third pivot axis.
 3. 52. The retractablevehicle step of Claim 51, wherein: said first support arm comprises aunitary support arm defining an inboard surface and an outboard surface,a maximum distance between said inboard surface and said outboardsurface defining a first thickness, said first support arm defining asubstantially vertical first side and a substantially vertical secondside, a maximum distance between said first side and said second sidedefining a first width, said first width being substantially greaterthan said first thickness.
 4. 53. The retractable vehicle step of Claim52, wherein: said second support arm comprises a unitary support armdefining an inboard surface and an outboard surface, a maximum distancebetween said inboard surface and said outboard surface defining a secondthickness, said second support arm defining a substantially verticalfirst side and a substantially vertical second side, a maximum distancebetween said first side and said second side defining a second width,said second width being substantially greater than said secondthickness.
 5. 54. The retractable vehicle step of Claim 51, wherein saidupper surface of said support bracket portion extends outboard of saidthird pivot axis.
 6. 55. The retractable vehicle step of Claim 54,wherein said support bracket portion further comprises a lower surfaceopposite said upper surface.
 7. 56. The retractable vehicle step ofClaim 55, wherein said lower surface of said support bracket portionextends outboard of said third pivot axis.
 8. 57. The retractablevehicle step of Claim 51, wherein said second support arm is insertedinto said opening at said fourth pivot axis.
 9. 58. The retractablevehicle step of Claim 51, wherein said support bracket portion comprisesa first side segment and a second side segment located on opposite sidesof said opening, wherein said first side segment and said second sidesegment comprise a unitary member.
 10. 59. The retractable vehicle stepof Claim 50, wherein at least one of said first support arm and saidsecond support arm further comprises a first end which forms at leasttwo spaced-apart coaxial bearing members suitable for pivotableconnection with respect to said underside of said vehicle.
 11. 60. Thestep assist of Claim 59, wherein said at least one of said first supportarm and said second support arm further comprises a second end whichforms at least two spaced-apart coaxial bearing members pivotablyconnected to said step member.